Remove effectful assertion

R=mstarzinger@chromium.org
BUG=461520
LOG=N

Review URL: https://codereview.chromium.org/955973003

Cr-Commit-Position: refs/heads/master@{#26857}

src/runtime/runtime-scopes.cc

@@ -931,13 +931,6 @@ static ObjectPair LoadLookupSlotHelper(Arguments args, Isolate* isolate,
   // property from it.
   if (!holder.is_null()) {
     Handle<JSReceiver> object = Handle<JSReceiver>::cast(holder);
-#ifdef DEBUG
-    if (!object->IsJSProxy()) {
-      Maybe<bool> maybe = JSReceiver::HasProperty(object, name);
-      DCHECK(maybe.has_value);
-      DCHECK(maybe.value);
-    }
-#endif
     // GetProperty below can cause GC.
     Handle<Object> receiver_handle(
         object->IsGlobalObject()

test/mjsunit/harmony/regress/regress-crbug-461520.js

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --harmony-proxies
+
+var fuse = 1;
+var handler = {
+  get: function() { return function() {} },
+  getPropertyDescriptor: function() {
+    if (fuse-- == 0) throw "please die";
+    return {value: function() {}, configurable: true};
+  }
+};
+
+var p = Proxy.create(handler);
+var o = Object.create(p);
+with (o) { f() }